The progress of the _Annihilator_ was gradually checked. More and more slowly it approached the moon. The mountains seemed even higher now, and the craters deeper. "What a terrible place," murmured Jack. "I shouldn't want to live there." "Me either," said Mark. "Can you see a place to land?" called Professor Roumann through the speaking-tube from the engine room to the steering tower. "Yes, we seem to be approaching a fairly level plateau," was Mr. Henderson's reply. "Very well, then, I'll start the repelling machine." The Cardite motor was stopped. The projectile was now being drawn toward the moon by the gravity force of the dead ball that once had been a world like ours. Slowly and more slowly moved the great projectile. There was a moment of suspense. Mr. Henderson threw over the steering wheel. The _Annihilator_ moved more slowly. Then came a gentle shock. The dishes in the galley rattled, and there was the clank of machinery. The Shanghai rooster crowed. "We're on the moon at last!" cried jack, peering from an observation window at the rugged surface outside. "Yes; and now to see what it's like," added Mark. "We'll go outside, and----" "Wait," cautioned Professor Roumann. "First we must see if we can breathe on the moon, and whether the temperature will support life. I must make some tests before we venture out of the projectile." CHAPTER XIX TORCHES OF LIFE The natural inclination of the boys to rush out on the surface of the moon to see what it was like was checked by the words of caution from Professor Roumann. "Do you think it would be dangerous to venture outside the projectile?" asked Jack, as he looked from the window and noted the rugged, uneven surface of the moon. "Very much so," was the answer. "According to most astronomers, there is absolutely no air on the moon, also no moisture, and the temperature is either very high or around the freezing point. We must find out what it is." "How can we?" inquired Mark. "I'll soon show you," went on the German. "Professor Henderson, will you kindly assist me." When it had been decided to come to the moon in quest for the field of diamonds, certain changes had been made in the _Annihilator_ to fit it for new conditions that might be met. One of these consisted of an aperture in the two sides of the projectile permitting certain delicate instruments to be thrust out, so that the conditions they indicated could be read on dials or graduated scales from within. "We will first make a test of the temperature," said Mr. Roumann, "as that will be the easiest." Accordingly a thermometer was put outside, and those in the air-craft anxiously watched the red column of spirits. The temperature was marked as seventy-five inside the _Annihilator_, but the thermometer had not been outside more than a second before it began falling.